fix: normalize malformed pull request authors (#87)

src/main.py

@@ -132,7 +132,18 @@ async def context() -> JSONResponse:
         )
     ]
     pr_models = [
-        PullRequest(id=p["id"], number=p["number"], title=p["title"], state=p["state"], user=(p.get("user") or {}).get("login", ""), url=p["html_url"])
+        PullRequest(
+            id=p["id"],
+            number=p["number"],
+            title=p["title"],
+            state=p["state"],
+            user=(
+                p["user"].get("login", "")
+                if isinstance(p.get("user"), dict)
+                else ""
+            ),
+            url=p["html_url"],
+        )
         for p in (prs_data or [])[:50]
         if isinstance(p, dict)
         and all(